1. Field of the Invention
The present invention relates to media ejection systems in printing devices, and, more particularly, to ejection systems for ink jet printers including support wings and media kickers, and methods for using such systems.
2. Description of the Related Art
Ink jet printers are used commonly for home and business printing applications. Ink jet printers are popular due to their low initial cost, low cost of operation, low energy use and quiet operating features. Ink jet printing involves ejection of tiny ink droplets through small holes, in a controlled manner, to create the desired image on the media. Ink is supplied from an ink reservoir to a printing head, which includes various passageways from the reservoir to one of a plurality of nozzle orifices. Energy is applied to the ink from an ink droplet generator near each orifice, which may include the application of electrostatic attraction, the application of oscillating forces from piezo elements, the application of heat from heating elements or the like. The printhead traverses back and forth in close proximity to the media being printed, and, as the various droplet generators are activated in the necessary pattern and sequence, the desired image is formed from the tiny ink droplets deposited on the surface of the media.
Laser printers are also used in both home and office applications. Although generally more costly than ink jet printers, laser printers are sometimes preferred for the perceived greater print quality and the faster printing speed available from laser printers.
For ink jet printers to compete more favorably with laser printers, it is necessary to increase the printing speed and the optical density of the printed image obtained from an ink jet printer. These performance increases in an ink jet printer must be achieved without increased occurrence of ink smear. Ink smear can occur when wet ink is contacted by the same piece of media, by another piece of media or by surfaces or devices in the printer.
It is known to support and delay printed media exiting the print area in an ink jet printer, to allow time for the ink to dry. Eject systems in ink jet printers are known to include movable wings along the edge of the media path to support the printed media from beneath, and kickers operated on the trailing edge of the media to assist in ejecting the media. Media supported by the edge wings may bow slightly, giving the media a degree of beam strength, while still remaining flat in the print zone. Supporting and handling media in this manner has been successful in reducing the incidence of smear for many common print job operations.
In some operating conditions, the devices intended to reduce the incidence of smear, namely the wings and kickers, can actually be responsible for increased incidence of smear, potential media jams, and/or slowed printer performance. For example, when printing in a draft mode, in which less ink is applied to the media, ejection systems using wings and kickers can slow overall printer performance, in that each cycle of the wings and kickers can require more time than necessary for the ink to dry. Printing banner paper or envelopes also can be slowed when wings and kickers are used.
Supporting banner paper or envelopes on edge wings can cause smear by urging the length of the media into direct physical contact with the printhead. When banner paper is supported on edge wings, after a considerable length thereof has passed through the exit system, the xe2x80x9cbeamxe2x80x9d collapses. The result can be bunching of the banner paper in the print zone, resulting in physical interference between the banner paper and the printhead. With narrower, more rigid media such as envelopes, support from beneath by an edge wing along one side of the envelope can cause the entire length of the envelope to rise upward along the surface of the wing and rearward thereof into the printing area. Even relatively limited upward movement of the top surface of the media can cause physical interference between the media and the printhead, since the normal spacing therebetween is quite small. When any physical interference occurs between the media and the printhead, smear, lateral displacement of the media, or a media jam can be the result.
What is needed in the art is a multifunction media eject system that provides different edge support and kicker operations, depending on the type of print job performed and the type of media upon which printing is performed.
The present invention provides a multi-function media eject system particularly useful for ink jet printers, that positions edge support wings and sheet kickers differently for different printing formats and for different media types, thereby reducing potential smear and paper jams, and improving overall printer performance.
The invention provides, in one form thereof, a media eject system for a printer with an edge wing for supporting an edge of media exiting the printer. The edge wing is movable between support and non-support positions. A kicker is provided for engaging a trailing edge of media and moving the media into an output tray. The kicker is movable between a retracted position and an extended position, and is operable to move the media into the tray by movement of the kicker from the retracted position to the extended position. A controller determines the media type and print format being used, and adjusts positions of the wing and the kicker at the start of a print job dependent upon the print condition.
In another form thereof, the invention provides a method for operating a media eject system of a printing device. Edge wings have a wings up position for supporting media exiting the printer and a wings down position providing no support to media exiting the printer. A kicker is provided for moving media, the kicker having a retracted position and an extended position and adapted for moving the media as the kicker is moved from the retracted position to the extended position. The method has further steps of determining a print condition for each print job, the print condition including at least one of a media type being printed and a printing format being used; and adjusting positions of the wing and the kicker in response to the print condition. The method selectively provides media support and kicker function for specific print conditions, and no media support and no kicker function for other specific print conditions.
In a further form thereof, the invention provides a method for operating a media ejection system during a print job in a printer, the media ejection system including edge support wings for supporting the media exiting the printer and a kicker for accelerating the media exiting the printer. The method steps include determining a print condition for the print job to be at least one of the media being an envelope, the media being banner paper and the print format being a draft printing mode. The method further includes adjusting the wings and the kicker to non-operating conditions in response thereto; and passing the media out of the printer without support by the wings and without acceleration by the kicker.
In still another form thereof, the invention provides a method of operating a printer having an eject system including wings for supporting sheets of media exiting the printer. The method steps include determining the type of media being printed and the print format being used; and moving the wings to non-supporting positions if the media is banner paper or envelope, or if the if the print format is draft.
In a still further form thereof, the invention provides a method of operating a printer having an eject system including a kicker for accelerating the sheets of media exiting the printer. The method steps include determining the type of media being printed and the print format being used; and moving the kicker to a non-operative position if the media is banner paper or envelope, or if the if the print format is draft.
An advantage of the present invention is providing a multi-function eject system control with common eject system hardware, and reduced potential for media jams in the printer.
Another advantage is improving speed performance for draft mode printing while also reducing potential for smear when printing envelopes or banner paper.
Still another advantage is adjusting acceleration of the media without the use of kickers; and providing certainty that the exit area of the printer is cleared.